| # SPDX-License-Identifier: GPL-2.0-only |
| |
| config HAVE_ARCH_KGDB |
| bool |
| |
| # set if architecture has the its kgdb_arch_handle_qxfer_pkt |
| # function to enable gdb stub to address XML packet sent from GDB. |
| config HAVE_ARCH_KGDB_QXFER_PKT |
| bool |
| |
| menuconfig KGDB |
| bool "KGDB: kernel debugger" |
| depends on HAVE_ARCH_KGDB |
| depends on DEBUG_KERNEL |
| help |
| If you say Y here, it will be possible to remotely debug the |
| kernel using gdb. It is recommended but not required, that |
| you also turn on the kernel config option |
| CONFIG_FRAME_POINTER to aid in producing more reliable stack |
| backtraces in the external debugger. Documentation of |
| kernel debugger is available at http://kgdb.sourceforge.net |
| as well as in Documentation/dev-tools/kgdb.rst. If |
| unsure, say N. |
| |
| if KGDB |
| |
| config KGDB_HONOUR_BLOCKLIST |
| bool "KGDB: use kprobe blocklist to prohibit unsafe breakpoints" |
| depends on HAVE_KPROBES |
| depends on MODULES |
| select KPROBES |
| default y |
| help |
| If set to Y the debug core will use the kprobe blocklist to |
| identify symbols where it is unsafe to set breakpoints. |
| In particular this disallows instrumentation of functions |
| called during debug trap handling and thus makes it very |
| difficult to inadvertently provoke recursive trap handling. |
| |
| If unsure, say Y. |
| |
| config KGDB_SERIAL_CONSOLE |
| tristate "KGDB: use kgdb over the serial console" |
| select CONSOLE_POLL |
| select MAGIC_SYSRQ |
| depends on TTY && HW_CONSOLE |
| default y |
| help |
| Share a serial console with kgdb. Sysrq-g must be used |
| to break in initially. |
| |
| config KGDB_TESTS |
| bool "KGDB: internal test suite" |
| default n |
| help |
| This is a kgdb I/O module specifically designed to test |
| kgdb's internal functions. This kgdb I/O module is |
| intended to for the development of new kgdb stubs |
| as well as regression testing the kgdb internals. |
| See the drivers/misc/kgdbts.c for the details about |
| the tests. The most basic of this I/O module is to boot |
| a kernel boot arguments "kgdbwait kgdbts=V1F100" |
| |
| config KGDB_TESTS_ON_BOOT |
| bool "KGDB: Run tests on boot" |
| depends on KGDB_TESTS |
| default n |
| help |
| Run the kgdb tests on boot up automatically without the need |
| to pass in a kernel parameter |
| |
| config KGDB_TESTS_BOOT_STRING |
| string "KGDB: which internal kgdb tests to run" |
| depends on KGDB_TESTS_ON_BOOT |
| default "V1F100" |
| help |
| This is the command string to send the kgdb test suite on |
| boot. See the drivers/misc/kgdbts.c for detailed |
| information about other strings you could use beyond the |
| default of V1F100. |
| |
| config KGDB_LOW_LEVEL_TRAP |
| bool "KGDB: Allow debugging with traps in notifiers" |
| depends on X86 || MIPS |
| default n |
| help |
| This will add an extra call back to kgdb for the breakpoint |
| exception handler which will allow kgdb to step through a |
| notify handler. |
| |
| config KGDB_KDB |
| bool "KGDB_KDB: include kdb frontend for kgdb" |
| default n |
| help |
| KDB frontend for kernel |
| |
| config KDB_DEFAULT_ENABLE |
| hex "KDB: Select kdb command functions to be enabled by default" |
| depends on KGDB_KDB |
| default 0x1 |
| help |
| Specifiers which kdb commands are enabled by default. This may |
| be set to 1 or 0 to enable all commands or disable almost all |
| commands. |
| |
| Alternatively the following bitmask applies: |
| |
| 0x0002 - allow arbitrary reads from memory and symbol lookup |
| 0x0004 - allow arbitrary writes to memory |
| 0x0008 - allow current register state to be inspected |
| 0x0010 - allow current register state to be modified |
| 0x0020 - allow passive inspection (backtrace, process list, lsmod) |
| 0x0040 - allow flow control management (breakpoint, single step) |
| 0x0080 - enable signalling of processes |
| 0x0100 - allow machine to be rebooted |
| |
| The config option merely sets the default at boot time. Both |
| issuing 'echo X > /sys/module/kdb/parameters/cmd_enable' or |
| setting with kdb.cmd_enable=X kernel command line option will |
| override the default settings. |
| |
| config KDB_KEYBOARD |
| bool "KGDB_KDB: keyboard as input device" |
| depends on VT && KGDB_KDB |
| default n |
| help |
| KDB can use a PS/2 type keyboard for an input device |
| |
| config KDB_CONTINUE_CATASTROPHIC |
| int "KDB: continue after catastrophic errors" |
| depends on KGDB_KDB |
| default "0" |
| help |
| This integer controls the behaviour of kdb when the kernel gets a |
| catastrophic error, i.e. for a panic or oops. |
| When KDB is active and a catastrophic error occurs, nothing extra |
| will happen until you type 'go'. |
| CONFIG_KDB_CONTINUE_CATASTROPHIC == 0 (default). The first time |
| you type 'go', you will be warned by kdb. The secend time you type |
| 'go', KDB tries to continue. No guarantees that the |
| kernel is still usable in this situation. |
| CONFIG_KDB_CONTINUE_CATASTROPHIC == 1. KDB tries to continue. |
| No guarantees that the kernel is still usable in this situation. |
| CONFIG_KDB_CONTINUE_CATASTROPHIC == 2. KDB forces a reboot. |
| If you are not sure, say 0. |
| |
| config ARCH_HAS_EARLY_DEBUG |
| bool |
| default n |
| help |
| If an architecture can definitely handle entering the debugger |
| when early_param's are parsed then it select this config. |
| Otherwise, if "kgdbwait" is passed on the kernel command line it |
| won't actually be processed until dbg_late_init() just after the |
| call to kgdb_arch_late() is made. |
| |
| NOTE: Even if this isn't selected by an architecture we will |
| still try to register kgdb to handle breakpoints and crashes |
| when early_param's are parsed, we just won't act on the |
| "kgdbwait" parameter until dbg_late_init(). If you get a |
| crash and try to drop into kgdb somewhere between these two |
| places you might or might not end up being able to use kgdb |
| depending on exactly how far along the architecture has initted. |
| |
| endif # KGDB |
